Livestock Science最新文献

The term discomfort is frequently used in for example biomedical studies, animal experimentation for farming purposes, animal welfare legislation, and ethical permits for animal experimentation. However, the concept of “animal discomfort” still remains unclear. Using the domesticated pig as a model, we performed a Walker and Avant concept analysis to develop an operational definition of animal discomfort. A total of 2,594 documents published in English were retrieved from Scopus database. Among them, 118 were retained for analysis as they contained either: 1 - a definition and/or measurement of discomfort in animals, including pigs; 2 – definition and/or measurement of pain, suffering, or sickness in pigs only. The literature review showed that animal discomfort intersects on three domains: physical, physiological, and mental discomfort. The presence of discomfort leads to a sense of uneasiness that results in behaviorally visible consequences comprising animals’ attempts to avoid or alleviate the source(s) of this affective state. Accordingly, our proposed operational definition of animal discomfort is: short- or long-lived negative affective state featured by physical, physiological and/or mental components, induced by internal or external stimuli, ranging from mild to severe, potentially occurring together with other negative affective states, and leading to avoidance or attempt to alleviate the source of uneasiness. Access to a shared definition of this central concept in animal welfare may be one initial step to facilitate legislation consistency, improve animal research integrity, and ultimately promote a more sustainable livestock production.

Despite the increasing use of automated milking systems (AMS), udder health performance of farms has only been limitedly quantified on farms with a milking robot. The objective of this study was to quantify udder health parameters (UHP) at test-day and at herd level on robotic farms using routinely collected somatic cell counts (SCC) from test-day data, and to study the correlations between these UHP. Additionally, the associations between UHP and season, year and farm size as well as the association between the daily milk production and the herd milk SCC were investigated. To this end, we collected SCC test-day data from 48 Belgian and Dutch farms participating in the milk recording of a local dairy herd improvement program. The UHP were calculated based on individual animal records at each test day over three years (2017 until 2019). These UHP included herd milk SCC, average heifer SCC, average cow SCC, percentage of high SCC, percentage of new high SCC, percentage of chronic high SCC, percentage of high SCC cows after calving, and percentage of recovery during the lactation. By fitting a linear mixed model effect for each of the different UHP, significant associations between the UHP and season, year and farm size were observed at test-day level. A poorer udder health was observed during summer compared to other seasons and generally, larger farms performed worse than smaller farms. Using a linear regression model, a significant negative correlation between herd average SCC and average daily milk production was found: an increase of 6,085 cells/mL was associated with a decrease of one kg of milk production. Finally, the cow-level UHP were averaged over all test days of the entire study period per farm to investigate the farm-level udder health performance and correlations between them. At the farm level, UHP analysis revealed most farms had poor udder health performance (i.e. the herd milk SCC, average heifer SCC, average cow SCC, percentage of new high and chronic high SCC were all higher than their target values) as proposed by Barkema et al. (2013). Both at the farm and at test day level, strong correlations were found among the UHP. Similar to studies on farms with conventional milking systems, a strong correlation between herd milk SCC and the percentage of new and chronic high SCC cows was found. This study gives new insights into udder health performance on farms with an AMS and provides veterinarians and other dairy industry stakeholders with concrete benchmarks for udder health performance on farms.

This study aimed to investigate the effect of increasing dietary protein during gestation on sows’ ability to re-establish body reserves and evaluate the impact on reproductive performance of multiparous sows. The experiment was carried out in a commercial Danish herd and 431 sows were included and allotted to one of five dietary treatments. The treatment period extended from the time of service until the sows were moved to the farrowing section, approximately 5 d before expected farrowing. Experimental diets were isoenergetic and contained increasing concentrations of dietary protein (standardized ileal digestible [SID] lysine [Lys]; 3.37 to 6.39 g/kg). Sow body weight (BW) and backfat (BF) were recorded at service, on d 28 and 84 of gestation, and one to three days post-farrowing. Live and stillborn piglets and piglet birth weight were recorded. Sow body protein and fat were estimated; however, body fat estimations were considered inaccurate. Moreover, the feed and Lys to BW gain ratios were calculated. In early gestation, the BW and body protein gain of parity 2 to 3 sows increased linearly with increasing SID Lys (P < 0.001), while in mid-gestation BW gain had a polynomic response to SID Lys (P < 0.001), showing that BW gain was maximized at 5.0 g SID Lys/kg diet. Above the maximal BW gain sows’ body protein gain reached a plateau (P < 0.001) and Lys to BW gain ratio increased (P < 0.001), indicating oxidation of excess protein. In contrast, sow BW and body protein gain of parity 4 to 5 did not change with increasing SID Lys in most gestation stages, indicating that maternal growth was limited by energy intake. Sow BF gain did not change with increasing SID Lys, even though increasing SID Lys presumably increased the energy costs for protein retention or oxidation. Sow reproductive performances were not affected by dietary treatment, showing that fetuses are highly prioritized. In conclusion, sows of parity 2 to 3 re-established more BW and body protein than parity 4 to 5, when fed increasing dietary protein (SID Lys) during gestation. The dietary concentration of SID Lys did not affect sow reproduction in terms of litter size and average piglet birth weight; thus, SID Lys should be kept low during gestation until approximately one week prior to farrowing, and yet allow sows to re-establish sufficient body reserves for mobilization in the following lactation.

Milk consumption plays a pivotal role in human nutrition, especially for children, due to its high protein, calcium, and vitamin contents that aid cognitive development. Nonetheless, potential hazards from heavy metal presence in milk, due to environmental exposure and intake through feed, have gained global attention. Given paucity of data we investigated the seasonal variation in the quantitative intake of heavy metals (cadmium: Cd, chromium: Cr, lead: Pb) by dairy cows in the South Indian megacity of Bengaluru, and the resulting heavy metal concentrations in milk and feces. The research involved 39 dairy farms across urban and peri‑urban areas, where 281 feed, 329 milk, and 183 feces samples were collected along with management data during monsoon (July 2020 - August 2020), winter (November 2020 – February 2021) and summer (March 2022 – June 2022) seasons. During the summer season, Cd concentration in lake fodder averaged 1.6 mg/kg DM, which was higher than the 0.6 mg/kg DM during winter and 0.9 mg/kg DM during the monsoon season. The higher concentration resulted in an increased daily Cd intake of 13.7 mg/cow/day. Similarly, Cr and Pb intake were also highest in summer (Cr: 46.3 mg/cow/day, Pb: 11.7 mg/cow/day), whereby for both elements the concentrations were higher in non-lake feed than in lake fodder. With the exception of a few milk samples, Cr and Pb concentrations were below threshold levels and did not compromise milk safety, and Cd levels never raised concerns. Nevertheless, elevated Cr and Pb concentrations (Cr: 9.8–16.9 mg/kg DM, Pb: 4.1–10.6 mg/kg DM) were determined in feces across seasons, potentially endangering the environment and reintroducing these elements into the food chain through manure application on agricultural land. Rather than uniformly discouraging the use of lake fodder in Bengaluru, authorities on the one hand should caution fodder usage in pollution-prone areas, and on the other hand take measures to reduce contamination levels at those sites. Furthermore, it appears necessary to implement more stringent control measures for other types of feedstuffs. Raising farmers' awareness of the problem of heavy metals in the food chain could promote their compliance with regulations without the need for complete feed bans, which are difficult to enforce in a highly contested urban environment.

This experiment aimed to determine the net energy (NE) content of a finishing pig diet containing Chickpea (Cicer arietinum) using indirect calorimetry and chemical composition methods. The study was carried out under a completely randomized design, with (i) diet with Soybean Meal and (ii) a diet with Chickpea. Eight barrows (n = 4 animals/diet) in the finishing phase with an average initial body weight (BW) of 88.8 ± 3.41 kg were housed in metabolism cages for 17 days, which included 10 days for adaptation and 5 days for collection of feces and urine for nitrogen and energy balance. On day 15, pigs were transferred to respiratory chambers and fed one of the two diets at 550 kcal ME/kg BW^0.6/day. Total feces and urine were collected, and heat production was measured for 36 h: 24 h (day 16) heat production in the fed state and 12 h (day 17) heat production in the fasted state. The NE of the diet containing Chickpea measured by the indirect calorimetry method was 2.913 kcal/kg dry matter (DM), while the NE of the diet containing Soybean Meal was 2.939 kcal/kg DM. The NE/ME ratios were 85 and 86 % for the diet containing Chickpea and Soybean Meal, respectively. The NE values for both diets, estimated according to the chemical composition methods, were 2,537 and 2,552 kcal/kg DM for the diet containing Chickpea and Soybean Meal, respectively. In conclusion, the average NE of the two diets estimated by the indirect calorimetry method in the present study was higher (382 kcal/kg DM average) than the values predicted from the chemical composition methods used to estimate NE.

This study was conducted to investigate the effects of supplementation of B vitamins, fat-soluble vitamins (ADE), and combination of B+ADE on beef quality parameters and antioxidant status. Forty young Nellore bulls were allocated randomly across four treatments: no vitamin supplementation (Control); B vitamins supplementation (B); fat-soluble vitamins supplementation (ADE); and ADE + B supplementation. At the end of a 140-day trial, samples were collected to perform analysis of meat quality parameters and status activity of antioxidant enzymes at 1 h, 24 h, 192 h and 360 h post mortem. Treatments had no significant on pH24h, sarcomere length, meat color (L*, b*, chroma) or fat color (L*, a*, b*) of the longissimus lumborum muscle at 24 h, 192 h and 360 h post mortem between treatments B, ADE or ADE+B in relation to the control treatment. Furthermore, no significant changes were observed in the redox form of myoglobin (OMb, DMb, MMb) 24 h post mortem. However, the ADE and ADE+B treatments resulted in a higher percentage of intramuscular fat in the longissimus lumborum muscle when compared to the control treatment. Greater myofibrillar fragmentation index at 24 h, 192 h and 360 h, higher levels of oxymyoglobin at 192 h and 360 h, lower levels of metmyoglobin at 360 h were detected in the ADE and ADE+B treatments when compared to the control treatment. Furthermore, ADE increased superoxide dismutase (SOD) at 192 h and ferric reducing antioxidant power (FRAP) at 360 h compared to the control treatment, while ADE and ADE+B treatments increased FRAP at 24 h and 192 h, and catalase (CAT) at 192 h Moreover, ADE and ADE+B treatments decreased glutathione peroxidase (GPx) at 24 h and decreased malondialdehyde (MDA) content at 24 h and 360 h when compared to the control treatment. The use of ADE and ADE+B favored the formation of oxymyoglobin, prevented the oxidation of myoglobin, increased the ferric reducing antioxidant power and impaired lipid oxidation at different periods of ageing.

Preventing cow-calf contact in rearing systems has been scrutinised. This descriptive study investigated the effects of full-time contact outdoors on pasture (FT-O), part-time contact indoors (PT-I), or no contact indoors (NC-I) on calf health, behaviour, growth and labour in a pasture-based dairy system. Cows (n = 55) were balanced pre-calving on parity (16 primiparous and 39 multiparous), milk production (35 weeks) of previous lactation (4497 ± 193.8 kg), breed and predicted calving date. Contact pairs bonded for 48 h, whereas NC-I calves were separated from cows immediately, and remained in individual pens for three days before grouping. The FT-O pairs moved outdoors at 5 ± 3.3 days, only separated from cows for milking twice daily. Part-time cows were milked once-a-day (8:00) and grazed outdoors post-milking, returning indoors to calves from 15:00–8:00 the following morning. The NC-I calves were assigned to a feeding plan offering up to 9.5 L/day of milk replacer via automatic feeder. All calves had Ad libitum access to water, concentrates and forage. For NC-I calves, weaning started at 48 days, taking 12 days, for contact calves it started at 58 days, taking seven days. From birth to three weeks post-weaning, animal health and labour were evaluated twice-weekly, weight and linear body measurements were recorded weekly and behaviour was recorded weekly (daily during weaning). Following this, weighing was carried out fortnightly. Faecal related issues were seen most often in contact calves than NC-I calves. The PT-I calves also experienced eye issues more often than NC-I and FT-O calves. Illness resulted in 26 % of FT-O calves being removed from experiment (none removed from NC-I and PT-I). The PT-I calves expressed the most abnormal behaviours throughout weaning. Contact calves vocalised more at weaning than NC-I (7.8 % vs 1.5 % of time). The NC-I calves weighed less at 28 (49.0 vs 55.5 kg), 56 (69.0 vs 82.1 kg), 70 (79.0 vs 87.1 kg) and 77 (81.8 vs 90.8 kg) days than FT-O and PT-I calves. Labour associated with calving was greater for the NC-I system (00:15:56 ± 00:00:35) than contact systems (00:01:39 ± 00:00:35). Weekly labour was greater for the FT-O system (00:01:29 ± 00:00:05) than NC-I and PT-I systems (00:00:44 ± 00:00:05), which were similar. Weaning labour was negligible for NC-I calves (computerised feeder), but 00:02:08 ± 00:00:09 for contact systems, which were similar. To conclude, pre-weaning calf growth and reduced labour at calving as a result of cow-calf contact is challenged by calf health and human welfare (related to daily labour) in the FT-O system and by calf behaviour and stunted post-weaning growth in the PT-I system. Thus, cow-calf contact in pasture-based dairy systems require further research to safeguard calf and human welfare.

Interest in dairy cow-calf contact (CCC) systems is growing, yet limited research had been focused on CCC in a pasture setting. Our study aimed to evaluate the performance of pastured dairy cows and calves with or without CCC through machine milk yield and composition, cow body condition score (BCS) and body weight (BW) decrease, and calf body weight gain (BWG). We also examined calf intake of concentrates, artificially reared calves’ milk intake, and the health of both cows and calves. Conducted on a commercial dairy freestall farm and summer farm in Norway from May to August 2021, the study included twenty cow-calf pairs: 17 Norwegian Red (NRF) and three NRF × Holstein crossbreeds. They were divided into two treatments: cow-calf contact (CC, n = 10) or early separation (ES, n = 10), each with two groups of five cow-calf pairs. CC pairs had full CCC on pasture until 6 weeks postpartum and part-time contact in weeks 7 and 8 (weaning). ES pairs were separated 1–3 h after birth, kept on separate pastures with no contact between ES cows and calves. ES calves’ received daily milk allowances of 12–14 L (weeks 0–6), reduced to 8 L (week 7) and further to 4 L (week 8). From week 9, all calves were denied access to any milk (ES) or cows (CC). During weeks 0–6, CC cows had a daily machine milk yield 23.7 kg lower/cow than ES cows. The difference was likely affected by nursing and other factors (parity and inhibited milk ejection), and persisted during weaning, with CC cows delivering 8.3 kg less/cow/day in weeks 10 and 11 postpartum. Fat and protein content in machine milk showed no significant difference, while lactose content was lower in milk from CC cows than ES cows (week 5 postpartum). CC cows had a lower BW decrease compared to ES cows (CC: 913 g/day, ES: 1415 g/day from pasture day one through week 9). ES calves had an average milk intake of 10.7 L/calf/day (weeks 0–6), and consumed more concentrates than CC calves. Calves’ daily BWG did not differ between treatments in weeks 0–6 (CC: 1340 and ES: 1250 g/day) and decreased for both treatments during weaning (CC: 1050 g/day, ES: 920 g/day in weeks 6–9). Inhibited milk ejection during machine milking was a challenge in CC cows, prompting oxytocin injections to prevent mastitis. Allowing calves full CCC or providing whole milk near ad libitum can result in similar BWG and health in calves. Further research should explore strategies to enhance milk ejection in pastured CCC cows.

Two experiments were conducted to evaluate the effects of a novel consensus bacterial 6-phytase variant (PhyG) on performance of broilers fed US type diets with reduced nutrients and energy. Each experiment utilized a completely randomized block design where four treatments were tested with 10 replicate groups, each treatment totaling 270 day-of-hatch male Ross 308 broilers. The diets were: 1), a nutrient-adequate control (PC) and 2), a nutrient and energy-reduced negative control (NC): PC minus 0.19 % avP, 0.23 % Ca, 0.045 % Na, up to 0.05 % unit dig AA and 37 kcal/kg ME and 3), NC with PhyG supplemented at 1,500 FTU/kg (PhyG1500) 4), PC minus 0.164 % avP, 0.201 % Ca, 0.037 % Na, up to 0.035 %-unit dig. AA and 29 kcal/kg ME plus the PhyG at 750 FTU/kg (PhyG750). Xylanase was included in all diets at 750 XU/kg with 25 kcal/kg of ME matrix applied. Experiment 1 diets (wholly vegetable) were based on corn-soybean meal with <2 % DDGs. Experiment 2 diets (conventional) were based on corn-soybean meal with <3 % DDGS and <4 % meat and bone meal. Diets were pelleted and fed ad libitum over four phases: starter (1–10d), grower (11–21d), finisher 1 (22–35d), and finisher 2 (36–42d). In both experiments, compared with PC, birds fed the nutrient and energy reduced NC exhibited reduced 42d BW and increased overall 1–42d FCR (P < 0.05). During all phases, in both experiments, PhyG at each dose-level produced growth performance measures that were by phase and cumulatively equivalent to PC. PhyG at 1500 FTU improved accumulative FCR (1–21d, 1–35d and 1–42d) in experiment 1, and 1–21d FCR in experiment 2 compared to PC. Similarly, PhyG750 and PhyG1500 increased (P < 0.05) tibia ash and carcass yield vs. NC to similar levels as PC. For all measures, response values were numerically highest with 1500 FTU/kg. In conclusion, the novel consensus phytase variant completely compensated for the reduction in avP, Ca, Na, dig AA, and ME respectively at each dose-level and maintained growth performance, carcass characteristics, and bone quality of broilers fed wholly vegetable or conventional US type commercial diets through 42 days of age, leading to reduced feed cost and production benefit.

Sows commonly suffered ROS due to increased energy demands and metabolic burdens during late gestation (LG) and lactation. Astaxanthin (Asta) is a potent antioxidant, which can enhance livestock health and productivity. Therefore, this study aimed to evaluate the effects of Asta on antioxidant status, reproductive outcomes in sows, and the growth performance of piglets. A total of 80 large white sows were randomly divided equally into dietary treatments supplemented with 0, 4, 8 and 12 mg/kg Asta from 85 days of gestation to 21 days of lactation. The results demonstrated that with increasing levels of dietary Asta, the concentrations of Asta in placenta, colostrum, and piglet liver significantly increased (P < 0.05), which notably reduced the levels of reactive oxygen species (ROS) and malondialdehyde (MDA), while significantly increasing total antioxidant capacity (T-AOC) and superoxide dismutase (SOD) activity in sow serum, placenta, colostrum, and piglet serum (P < 0.05). In addition, Asta supplementation significantly increased the number of live births (NLB) in sow and average daily gain (ADG) of piglet with a significant improvement in placental angiogenesis and duodenal development status of piglets (P < 0.05). Overall, dietary Asta in sows can be transferred to piglets through the placenta or milk, which can improve sow reproductive outcomes and piglet growth by reducing oxidative stress during late gestation (LG) and lactation.